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OpenAI's GPT-6.1 Sol matches Astra at one-fifth cost

OpenAI's GPT-6.1 Sol matches Astra at one-fifth cost

3 Key Points

  1. What happened

    OpenAI announced GPT-6.1 Sol on September 29, saying it matches GPT-6 Astra on the DeepSWE v1.1 coding and GDP.pdf document benchmarks at one-fifth the cost per task, and beats Anthropic's Claude Opus 5.5 on AutomationBench at about one-third the cost.

  2. Why it matters

    Matching GPT-6 Astra's benchmark performance at one-fifth the cost per task suggests near-flagship results may now be available at a far lower price point.

  3. What to watch

    GPT-6.1 Sol's improvements are described only through OpenAI's own alignment evaluations, so whether it holds up in real use is still the test.

WHO IT HITSTeams building applications on OpenAI's API and businesses running coding or document-heavy workflows on ChatGPT are the first to see the cost-per-task difference, and the pricing likely matters most to those running these tasks at high volume.

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Context & Analysis

OpenAI describes GPT-6 Astra as its highest-performing model and positions GPT-6.1 Sol for users who want to handle important work more frequently, or for API users building and running applications at scale. The gap between the two is framed less around raw capability than around cost: on the DeepSWE v1.1 coding and GDP.pdf document-reading tests, OpenAI says GPT-6.1 Sol reaches GPT-6 Astra-equivalent performance at one-fifth the cost per task. On AutomationBench, which measures multi-step workflow execution, OpenAI says the medium-thinking GPT-6.1 Sol beats Anthropic's Claude Opus 5.5 at about one-third the cost, and on OSWorld 2.0, which measures computer-operation ability, it says the score gap with GPT-6 Astra narrows to 2.1 points at about one-seventh the cost per task.

The timing is notable: GPT-6.1 Sol arrives just one week after GPT-6 Sol, and OpenAI reports that in its own alignment evaluations GPT-6.1 Sol improves substantially over GPT-6 Sol and approaches GPT-6 Astra. That framing sits alongside reports from The Wall Street Journal and Reuters that OpenAI withheld the launch of GPT-6.1 Astra, planned for October, over safety concerns.

For developers and businesses, the practical question is whether OpenAI's own benchmark figures translate into day-to-day work, since the comparisons rest on OpenAI's published evaluations. The models reach the same plans and the same API, so the outcome likely hinges on whether teams see the stated cost-per-task advantage in their own workloads rather than on the benchmark scores alone.

FAQ
Which ChatGPT plans can use GPT-6.1 Sol?
It is available from launch day on the Plus, Pro, Business, Enterprise, and Edu plans through ChatGPT Work and Codex. It is not yet available in Chat.
How much does GPT-6.1 Sol cost via API?
Input is $2 per 1 million tokens, cached input is $0.10, and output is $10.
Why is GPT-6.1 Astra not out yet?
OpenAI held back the launch of GPT-6.1 Astra, planned for October, amid safety concerns, according to reports by The Wall Street Journal and Reuters.

Also reported by AI Watch (Impress), GIGAZINE AI, OpenAI Blog, THE DECODER, TechCrunch AI

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